| dc.contributor.author | Glover, Kathleen Elizabeth. | en_US |
| dc.date.accessioned | 2014-10-21T12:35:41Z | |
| dc.date.available | 1995 | |
| dc.date.issued | 1995 | en_US |
| dc.identifier.other | AAINN05200 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55034 | |
| dc.description | For this thesis the genetic origins of wheat mitochondrial tRNAs were studied. The primary focus of the research was the identification of the non-mtDNA-encoded tRNAs present in a wheat mitochondrial RNA preparation, as the wheat mtDNA-encoded tRNA population had already been extensively examined and found to contain far fewer than the number of tRNAs required for translation of mitochondrial messenger RNAs. | en_US |
| dc.description | Sixteen tRNAs were identified through partial sequence analysis that show greatest sequence identity (70.5-100%) with plant cytosolic isoaccepting tRNA sequences and only 46-57.8% sequence identity with isoaccepting tRNAs encoded by plant mtDNA. These tRNAs are conventional in their primary sequences and secondary structures. Oligonucleotide probes specific for all of these tRNAs hybridized to both mitochondrial and cytosolic RNA preparations and the majority of these tRNAs were present in the mitochondrial RNA fraction at levels greater than determined for a cytosolic tRNA not required by wheat mitochondria for protein synthesis. Two of the tRNAs identified (tRNA$\rm\sp{Asp}$ and tRNA$\rm\sp{His}$) are redundant with respect to the tRNAs encoded within the mitochondrial genome. However, the amount of time cytosolic-like tRNA$\rm\sp{Asp}$ present in the wheat mitochondrial RNA preparation could not be distinguished from that of a cytosolic tRNA not required for use in mitochondrial protein synthesis and therefore this tRNA may not function in mitochondrial translation. The presence of both a mtDNA-encoded tRNA$\rm\sp{His}$ and a cytosolic-like tRNA$\rm\sp{His}$ in the tRNA population may represent an intermediate stage in the evolution of the wheat mitochondrial tRNA population. | en_US |
| dc.description | The wheat mitochondrial tRNA population as characterized to date includes 17 mtDNA-encoded tRNAs (10 "native" (tRNAs that have 65-80% sequence identity with homologous eubacterial and chloroplast tRNAs) and 7 "chloroplast-like" (tRNAs that have $>$90% sequence identity with chloroplast tRNAs)) and at least 13 "cytosolic-like" (nDNA-encoded) tRNAs. Assuming standard wobble rules for codon/anticodon base pair recognition, at least five tRNAs remain to be identified. Moncot, dicot and liverwort mitochondrial tRNA populations have significant differences with respect to the genetic origin of their tRNA species. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1995. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Biology, Molecular. | en_US |
| dc.title | The genetic origins of transfer RNAs in wheat (Triticum aestivum) mitochondria. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
